2007 Annual Audit

TYPES OF HERNIAS:

In 2007 there were 410 patients who had 465 hernia operations including 55 bilateral inguinal hernia repairs. They ranged in age from 15-93 years. A similar number were treated in 2005 and 2006.

Over 90% were inguinal. The remainder were umbilical (the commonest), epigastric, femoral, incisional, spigelian and recurrent inguinal hernias.

A small number of patients require more urgent operations after their initial consultation because of an episode of incarceration or increasing pain.

We treated very few strangulated inguinal hernias. This may be because we are more of an elective practice. However we believe the incidence of strangulation is being reduced because hernias are being treated earlier. The patients are better informed and because of the lower risks of surgery are more agreeable to having it carried out at an early stage.

There were 15 recurrent inguinal hernias operated on. This is a decrease in number from previous years. None of the recurrent inguinal hernias were our own operations. Most of the recurrent hernias operated on did not have a previous mesh reinforcement.

Over 90% of patients were treated as a day case. Most overnight stays were for family reasons or infirmity. However age and infirmity were not a bar to day surgery as there were a high proportion of 70 to 90 year olds treated as a day case.

Most of the hernias were classified as small to moderate size and reducible. There were a significant number of irreducible hernias and hernias which descended into the scrotum. Some could have been classified as giant hernias. This only occasionally proved to be a bar to day surgery and Local Anaesthesia.

In young people the majority of inguinal hernias were indirect. With ageing, the proportion of direct inguinal hernias increased.

With indirect hernias there was often an associated lipoma protruding through the deep ring. In a significant number this lipoma – consisting of extraperitoneal fat, simulated a hernia and could not be distinguished clinically or by ultrasound from the sac of a hernia. The fat of a lipoma cannot be distinguished from intraperitoneal omentum by ultrasound. The lipomata were just like a hernia. They might cause pain and even strangulate.

ANAESTHETIC TECHNIQUE:

Hernias were repaired using direct Local Anaesthetic infiltration and intravenous sedation. The Local Anaesthetic was a combination of Xylocaine (Lignocaine) 1-2% with Adrenaline 1 in 200,000 mixed with 0.5% Marcaine plain (Bupivacaine). This makes a solution of Adrenaline 1 in 400,000, a volume of 40 ccs. The recommended doses were never exceeded. The percentages were sometimes adjusted for bilateral hernias. Extra volume was obtained by using extra 0.9% Saline up to 10-15ccs. There were no adverse outcomes from the Local Anaesthetic such as arrhythmia, fits, respiratory depression or any evidence of over dosage.

The Local Anaesthetic was injected by the Surgeon after the initial dose of intravenous sedation by the Anaesthetist. The sedation was deep enough for the patient not to feel the first injection. Following this sedation was minimal and most patients were able to talk and cough during the procedure.

Each Surgeon has his particular technique and preferences for dosage, which are usually discussed with the Anaesthetist. In turn the Anaesthetist usually discusses the technique that they are going to use to ensure that there is adequate co-operation.

Conversion to a full anaesthetic occurred only on a few occasions – sometimes associated with obesity and difficult exposure particularly with a patient with extreme anxiety or restless leg syndrome, which appeared to be associated with sleep apnoea.

SURGICAL TECHNIQUE:

1. Indirect hernia. The indirect sac is reduced or excised depending on the circumstances.
2. For direct hernias – the sac was reduced and imbricated using non-absorbable suture.
3. Lipomatas. These were always removed.

THE MESH:

A Polypropylene 3 x 6-inch mesh was used in most cases and tailored to suit each patient.

This was usually stapled into position as an onlay to form a shutter mechanism at the deep ring.  A similar technique was used for both direct and indirect hernias.

Occasionally for hernias with a large deep ring, or for recurrent hernias, the mesh was rolled up into a plug to insert into the defect. Thus the repair was carried out without producing tension. A mesh plug was used routinely for femoral hernias. There were no complications from the mesh and no meshes needed to be removed. An antibiotic cover was not used for inguinal hernias routinely.

It is felt by some that the increasing use of mesh has led to an increase in numbers of chronic post-operative hernia pain syndromes. We do not appear to have encountered this problem. As a result of the pain many different types of meshes are being advocated. We will be a publishing a review of meshes in the near future.

Meanwhile the Melbourne Hernia Clinic has been using the same type of mesh for the last twenty years – the Polypropylene onlay mesh and we have been very happy with this.

CO-MORBIDITIES:

The ageing population and the prevalence of cardiovascular disease, implants, stents and valve problems together with patients neurological disorders have placed an increasing onus on the treating Surgeon to be absolutely sure about all medications and conditions before proceeding to surgery. We documented in our Audit which patients required adjustments of medication or active assessment prior to surgery to exclude particular problems. It was found that in the over 50 year olds some adjustment would be required in approximately 20% of cases, for example blood-thinning agents or Diabetic medication.

Despite this it was found that very few patients were rejected for surgery or had a problem as a result of an oversight.

FOLLOW UP:

On the day of surgery patients are able to walk from the hospital and are driven home – often one or two hours away. The Local Anaesthetic is still in effect so there is minimal pain making transport easy.

Several patients felt faint even before surgery, on the way out of the Day Surgery, at home that night or the next day. There were no complications as a result of this. This issue is carefully explained to patients. Fainting was felt to be a vasovagal response. The incidence of this seems to be decreased as we pay more attention to avoiding this problem. Most Anaesthetists insert an intravenous line and give 1 litre of fluid (0.9% normal Saline). We feel this has a beneficial effect.

All patients contacted the Surgeon the next day on his mobile number to inform him of their progress, for reassurance and advice regarding analgesia or the dressings. All patients were reviewed within ten days of surgery. Many of the patients did not require further review. If considered necessary – for example with undue swelling, bruising or anxiety a further appointment was made.

There was virtually a zero incidence of post-operative vomiting. This was particularly pleasing in that many patients had previously vomited as a result of surgery under General Anaesthesia, and this had been or was one of the reasons they had sought us out.

RESULTS:

POST-OPERATIVE PAIN:

Oral painkillers were used. The need for parenteral medication was rare.

1. The main analgesics used were Panadeine Forte, Panadeine, Panadol or Digesic. Anti-inflammatory agents such as Neurofen or Neurofen Plus were also sometimes used in combination. Patients were warned of the constipating effects of Codeine and were told to use laxatives as required.
2. It was found that many patients required no painkillers at all following the surgery. Most patients took painkillers for one or two days, often sporadically and intermittently. It was unusual for painkillers to be needed for more than three or four days.
3. Overall the majority of patients did not feel that pain was a significant factor.

HAEMATOMAS & BRUISING:

Bruising about the area was fairly common but of minimal significance. It was most pronounced with large inguino-scrotal hernias. There was an occasional haematoma, which formed. The haematomas occasionally in less than 1% of patients, required aspiration. These usually occurred in patients with giant inguino-scrotal hernias.

The incidence of seromas with the epigastric and umbilical hernias was low.

Pleasingly the incidence of post-operative bleeding requiring surgical intervention or readmission was 0. This is particularly important in day case surgery. There was one patient who required reapplication of the dressing by a family member at night.

We believe that a thorough closure of the wound in several layers is important in preventing this problem.

However we did recognise that bruising occurred in more than 1% of patients and always alerted the patients to the possibility.

The amount of post-operative swelling did surprise some patients – together with bruising. However careful explanation before and afterwards was reassuring. In these patients extra visits post-operatively were required.

WOUND INFECTION:

An antibiotic cover was not used routinely.

The low wound infection rate of less than 1% was particularly pleasing. None of the infections led to a serious problem. In the few cases of infection Local Anaesthetic into the wound and a small nick allowed drainage, which would occur over a few days. Antibiotics were given at that time. There was no incidence of mesh complications from infections.

FEMORAL NERVE BLOCK:

About one patient a year gets a femoral nerve block from the Local Anaesthetic and this means they cannot leave the Day Surgery Centre for a few hours because it is difficult to walk. No serious outcomes as a result of this problem.

BLOOD THINNERS:

One serious problem, which could have led to a serious outcome, was a patient who had been placed on Warfarin due to cardiac problems and took twice the dose of Warfarin by mistake for several days until the problem was realised and reversed. He did get severe bruising but interestingly there were no problems with the hernia wound.

We found that a great deal of care was needed in sorting out of the blood-thinning medications. Many patients are now on Aspirin routinely and Warfarin for problems such as cardiac valve or cerebrovascular problems. Also antiplatelet medication such as Plavix (Clopidogrel) is commonly used. We work closely with other treating Specialists in deciding the regime for managing these problems during surgery.

We no longer insist that patients cease Aspirin prior to surgery. When Warfarin or Plavix is stopped the advice may be for example – with atrial fibrillation to just stop the agents and not replace them with a low molecular weight Heparin such as Clexane. On other occasions Clexane is advised for three or four days before the procedure – not given on the day of the procedure or until that night, and then instituted again for another couple of days whilst the regular blood thinning agent is reintroduced. Some hospitals now have a hospital in home where a visit by the doctor or nurse practitioner administers the injections.

URINARY:

No patients require a urinary catheter. Despite many of the elderly patients having significant urinary problems and there being a reasonable number of young anxious males who are a potential candidate for this problem. It was felt that the use of Local Anaesthetic and early mobilisation negated against this problem.

It was noted recently in an article that all patients having a hernia repair in a particular series, had a urinary catheter inserted. We deplore the necessity for this.

RESPIRATORY COMPLICATIONS:

These were exceedingly unusual.

CENTRAL NERVOUS SYSTEM COMPLICATIONS:

We found that the Local Anaesthetic technique and light sedation meant that there was very little confusion particularly in the elderly patients.

CARDIO-VASCULAR COMPLICATION:

We had no problems with this despite many patients having a history of auricular fibrillation, ischaemic heart disease, stenting etc.

BOWEL:

Probably the most frequent reason for an unexpected call was the patients getting constipated and becoming anxious despite previous explanation and instruction. There were no serious problems as a result of this. Reassurance and further advice regarding laxatives or even a suppository always resulted in a satisfactory outcome.

DEEP VENOUS THROMBOSIS & PULMONARY EMBOLISM:

In the last ten years there has been only one case of deep venous thrombosis and pulmonary embolism. This was in a patient who had a previous history of deep venous thrombosis. We do not take action or preventative measures regarding deep venous thrombosis apart from having a mobile patient during the procedure and afterwards. However if there is a risk factor e.g. past history of deep venous thrombosis, normal precautions are instituted.

CONCLUSION:

The results for hernia repair for the year 2007 have been pleasing. They were in line with our results from the previous years 2005 and 2006.

The first aim in any surgical practice is to have a low incidence of complications. We found that this goal was achieved as exemplified by infection rate, deep venous thrombosis, acute retention of urine, respiratory, cardiovascular and bowel problems. There was a low incidence of bleeding complications.

Moreover we found that overall, recovery following surgery was excellent. There was little need for prolonged painkillers. There was rapid mobilisation and return to work. The day surgery concept was successful. We were of the opinion that the pain, rate of recovery and return to work were comparable and even superior to those attributed to keyhole surgery (laparoscopic). Two important advantages of our method are that the surgery is performed under Local Anaesthetic and the cost factor, particularly with non-insured patients.

The incidence of recurrence of inguinal hernias has been very low. As well we noted the incidence of recurrent hernias from other Surgeons had also decreased in number. We put this down to increasing use of mesh.

We found that we were pleased with these results although not every patient got back to work quickly. We did find that many people were able to get back to a sedentary type of job even after one or two days.